The invention relates to a device for locking and unlocking a cover or lid on a frame by means of a key.
It can be applied to roadway equipment such as a manhole.
Already known in the art is such a device that comprises a lock integral with the cover having an access opening in the lock for the key. This key comprises an arm having at its end a socket-forming part allowing the lock to be operated, when the key is inserted into the opening of the cover, from a locked position in which a locking bolt is held confined in a locking bolt receiver of the frame to an unlocked position for which the locking bolt is released from the receiver and the key is held confined in the opening of the cover. The lock also comprises a rotor mounted in rotation in the cover and accessible through the opening of the cover, the rotor being coupled to the locking bolt perpendicular to said bolt. When the key is inserted into the cover with the cover in the locked position on the frame and is operated to unlock the cover from the frame, the assembly composed of the rotor and the locking bolt pivots from its position confined in the receiver to its position released therefrom.
This known device has the disadvantages of using rather large number of components, making it relatively complex and resulting in risks of clogging, which could alter the operation of this device.